CLEVELAND -- Former Chicago Bears coach Marc Trestman and Raiders quarterbacks coach John DeFilippo are expected to be involved in the Browns' offensive coordinator search and the team could start interviews early next week, according to sources.

The Browns are taking this week to evaluate the offense in light of Kyle Shanahan's departure amid whispers of dissatisfaction with the Browns' personnel department and the quarterback situation. Wide-ranging meetings with personnel execs and coaches evaluated the team's quarterback situation and Johnny Manziel's place in it.

The Browns formally announced Shanahan's resignation and quarterback coach Dowell Loggains' firing, saying Shanahan's departure is "in the best interest of the Cleveland Browns" after conversations with him this week. Moving on from Loggains was difficult but necessary, coach Mike Pettine said in a statement.

"Our focus quickly turns to finding an outstanding coach to lead our offense and I am confident we will bring in highly qualified individuals to help us develop, improve and achieve the success we are all seeking," Pettine said.

Shanahan said in the Browns' release that he regrets how "the inner workings of the organization were represented publicly over the last few days," likely referring to a Cleveland.com report on Tuesday that Shanahan was willing to accept a lateral job to get out of Cleveland, and that at least one non-coaching staffer was suggesting play calls via texts to the sideline. The NFL is investigating the matter.

DeFilippo, who talked with coach Mike Pettine about the offensive coordinator job last year that went to Shanahan, has acquitted himself well after working with Derek Carr, who threw for nearly 3,300 yards, 21 touchdowns and 12 interceptions as a rookie.

Trestman, who was offensive coordinator and quarterbacks coach of the Browns in 1988-89, is known as a good offensive mind, but his Bears limped to a 5-11 finish despite elite playmakers, though it's noteworthy Jay Cutler wasn't his style of quarterback. He prefers a quarterback suited for his West Coast system, of which the Browns have principles from Shanahan's offense.

Candidates for the job might be asked these two things:

1. Can you make Manziel better?

2. How well can you work with different styles of quarterbacks, Manziel or otherwise? This gives the Browns flexibility with the position.